Abstract: A vent cap for use in a recombinant battery which includes a hollow barrel configured for gas-tight insertion into a vent hole in a battery cover. A retaining flange is formed at the closed end of the barrel, and a one-way relief valve formed on the barrel near its closed end. A layer of a polyalkylene explosion attenuating material surrounds the outside of the barrel below the flange and surrounding the relief valve. The polyalkylene material provides effective attenuation of explosions that occur in the vicinity of the relief valve. The invention further provides a vent cap assembly wherein the foregoing vent cap is mounted on a plastic vent cover of an otherwise conventional battery container.

Abstract: An electric storage battery according to the invention has a porous explosion attenuating material disposed within a head space of the battery case over the electrode elements. The attenuating material forms a layer or lining on the inner surface of the top wall of the case, and preferably also on the inner surface of the upper ends of each side wall between the electrode elements and the top wall. The interior of the head space remains open. Such an explosion attenuating material is effective to limit pressure build-up resulting from ignition of said gases within the case.

Abstract: A porous compressible plastic material is inserted into the head space above the cells in a storage battery to attenuate the explosion of combustible gases accumulating therein. The attenuation material is distributed to create a unique bimodal pore distribution, including a major proportion of small pores effective in attenuation and a minor proportion of large pores effective in gas and electrolyte management. Both open cell and fibrous materials may be utilized.

Abstract: A porous compressible plastic material is inserted into the head space above the cells in a storage battery to attenuate the explosion of combustible gases accumulating therein. The attenuation material is distributed to create a unique bimodal por distribution, including a major proportion of small pores effective in attenuation and a minor proportion of large pores effective in gas and electrolyte management. Both open cell and fibrous materials may be utilized.

Abstract: A porous compressible plastic material is inserted into the head space above the cells in a storage battery to attenuate the explosion of combustible gases accumulating therein. The attenuation material has a unique bimodal pore distribution, including a major proportion of small pores effective in attenuation and a minor proportion of large pores effective in gas and electrolyte management. Both open cell and fibrous materials may be utilized.